Triacylglycerol Reactions: Hydrolysis - Video Tutorials & Practice Problems
On a tight schedule?
Get a 10 bullets summary of the topic
1
concept
Triacylglycerol Reactions: Hydrolysis Concept 1
Video duration:
3m
Play a video:
In this video, we're gonna take a look at a tr ayl glycerol reaction in the form of hydrolysis. Now, hydrolysis can be either acidic or basic. In this first video, we're gonna look at acid catalyzed hydrolysis. Now, under this type of reaction, an estra bond is hydrolyzed to create a glycerol molecule, add three fatty acids. Now, here we're gonna say to curse step wise in the presence of a strong acid. The acids are typically hydrochloric acid or sulfuric acid. When we say step wise, that means that all three fatty acids don't come off all at once. First, we do hydrolysis of the first ester linkage to break off the first fatty acid. Then the second one occurs and then the third one occurs. In this illustration here, we're going to show our final products as having three fatty acids. We're gonna know that they all didn't come off all at once. This is the end result of going through three successions of acid catalyze hydrolysis to get rid of all three fatty acids. Now, here, if we take a look, we have our astro linkages here in red, we're using water and H plus, remember hydrochloric acid and sulfuric acid are strong acids in an aqueous environment. You typically see them represented as H plus, you could still see H2O over HCL or H2O over H two. So four. But typically, again, we see these two strong acids in this form here. Now what happens is our ester linkage is cut. So we cut these linkages when we cut these linkages, the oxygen that is part of my Glycerol molecule in blue that oxygen gains a hydrogen. And in that way, we've created our oh groups for Glycerol. So we've just created our Glycerol molecule here and then our fatty acid. Remember a fatty acid has a hydrocarbon tail and then it has a carbolic acid head to make this into a carbolic acid. We add oh to my carbon group. This is a hydrolysis. We're using water to cut the ester linkage. We're basically adding water back and h on the Glycerol oxygens oh on the carbonyl carbons. Now here, besides acid catalyzed hydrolysis, we have enzymatic hydrolysis. Now, this is a similar reaction done under milder conditions that instead uses the digestive enzyme lipase. So if we were to use the enzymatic approach, we'd use lipase instead of an acidic environment. This would still create our Glycerol molecule and three fatty acids, we put it here because we're essentially making the same products. The pathway to get to them is different, but we're still making the same products at the end. So just remember whether you're using acid catalyzed hydrolysis or enzymatic hydrolysis. Your products will be a Glycerol molecule and three fatty acids.
2
example
Triacylglycerol Reactions: Hydrolysis Example 1
Video duration:
1m
Play a video:
Here in this example, question, it says, draw the fatty acid products for the following reaction. So here we have our tri glycerol molecule or our triglyceride. We're using H two over our strong acid hydrochloric acid. We know that in essence, what happens here is that we're gonna sever our ester linkage is here, the oxygens that are part of our Glycerol molecule, they gain an H and then these carbon groups here, they're going to gain ohs to make our three fatty acids. So we're gonna do here is we're gonna write them out. So we're gonna have our ohs getting attached to these carbonel groups, right? So 123456. And so there goes one fatty acid there, let's see, 123, 123 and we have one here and then we have this pie bond. There goes my other fatty acid. And then finally, we have here, 12345, 12345. So those my three fatty acids that I've made. All right. So we can make this Glycerol molecule here and then these three individual fatty acids, they're all different from one another. So we don't have to draw them up. We won't draw them all the same way. We have three distinct types of fatty acids within this T product.
3
Problem
Problem
Provide the common name of the fatty acids produced from the enzymatic hydrolysis of the following triacylglycerol.
A
Palmitoleic acid
B
Lauric acid
C
Palmitic acid
D
Myristic acid
4
concept
Triacylglycerol Reactions: Hydrolysis Concept 2
Video duration:
1m
Play a video:
Now, so pod application represents base catalyzed hydrolysis. Because of this, we're gonna say under this reaction, the hydroxide ion leaves the ester bond to create salts of the fatty acids and glycerol. If we take a look here, we have our ester linkages, these red bonds here, they're gonna be severed when we do. So, po application, we're using our sodium hydroxide and some heat. In this case, we're gonna add hydrogens to the oxygens that help to make the glycerol molecule. And we're gonna say here we're making salt of the fatty acids. That means we're not gonna make carbolic acid fatty acids. We're gonna make carboxylate and ions. So basically, we're gonna have negatively charged oxygens. And because the metal that's formed with the base is N A, we have N A positive near it. So these will represent our three salts of the fatty acids. Now, here we're gonna say the salts of the fatty acids are used in the creation of soaps. So this is one important application of saponification of a triglyceride molecule. It helps in the creation of soaps that we use. We're gonna say here when sodium hydroxide is used as our base. This helps to make a solid soap. And then if we use potassium hydroxide koh that helps us to make liquid soap. So, again, so modification represents base catalyzed hydrolysis in this instance of a triglyceride or tri is glo glycerol molecule. And we're gonna say that it's important in the creation of soaps and based on the type of base that you're using, you can either make hard soap, a solid soap or you can make a liquid soap.
5
example
Triacylglycerol Reactions: Hydrolysis Example 2
Video duration:
2m
Play a video:
In this example, question, it says draw the starting trio glycerol used when it's complete basic hydrolysis, created two la salts, one palmitate salt and a glycerol molecule, right? So here we're working backwards. And what we're gonna say first is that these two salts came from fatty acids. Here, this laide salt comes from loic acid and this palmitate salt came from palmitic acid. Now, both of these fatty acids represent saturated fatty acids. Uric acid has 12 carbons and no py bonds. And then palmitic acid has 16 carbons and no py bonds. Now, here we're working backwards. We're gonna start out with our Glycerol base. So we have ch two chch two and we're gonna say they're connected to oxygens to create our starting material. We're gonna make ester linkages. So these oxygens are connected to the carbon eels of these fatty acid chains. So uric acid or laurite salts, we're gonna be the first two. That's 12 carbon. So 2468, 1012. And we do it again, 2468, 1012. And then finally, the last one is 16 carbon. So 2468, 1012, 1416. So this would represent our starting material, our our triglyceride molecule or our tri glycerol molecule. So again, we're just working backwards knowing what the salt was in terms of its fatty acid form is essential to determine how many carbons it possesses, how many p boss it connects it possesses. Then from there, we just have to make extra linkages between the fatty acids and the glycerol base, right? So the glycerol part or that connects the tr the fatty acids to it. Right. So, just keep that in mind when asked to figure out what our starting material would be.
6
Problem
Problem
The salt of a fatty acid has its ending of “ic acid” changed to “ate”. Based on this information provide the name of the salt created from the following saponification reaction.
A
Potassium Laurate
B
Sodium Oleate
C
Potassium Myristate
D
Potassium Lactate
Do you want more practice?
We have more practice problems on Triacylglycerol Reactions: Hydrolysis